Margot Kidder died at her home in Montana on Sunday at the age of 69, the Franzen-Davis Funeral Home and Crematory announced in a statement. TMZ was the first to report Kidder’s death. No cause of death has been disclosed as of yet. CNN reported that Kidder’s manager said that she died peacefully in her sleep.

Kidder is most famous for her portrayal of the tenacious and lovable Daily Planet reporter Lois Lane in the 1978 movie Superman. She starred with Christoper Reeve, who played the title character, and she reprised the role for three more films opposite Reeve in the blockbuster franchise through the 1980s. She was beloved for the role and on Monday her name quickly shot to the top of Twitter’s trending topics as fans paid tribute to her and shared their favorite clips of her from the Superman movies.

One particularly popular clip from the the 1978 movie shows Kidder as Lane dangling from a helicopter that’s hovering next to a New York City skyscraper, before losing her grip and plummeting toward the street below. Reeve as Superman comes flying in and catches her, saying, “Easy, miss. I’ve got you.”

A native of Canada, Kidder also appeared in the 1975 film The Great Waldo Pepper, and co-starred with James Brolin in 1979’s The Amityville Horror. Kidder struggled with bipolar disorder and in 1996 suffered a very public breakdown that left her temporarily homeless. She went on acting though, appearing in numerous TV shows, like Smallville and The L Word, and onstage including an appearance in a production of The Vagina Monologues.

Margot Kidder’s name rocketed to the top of Twitter’s trending topics on Monday after news of her death broke. Fans flooded the social media platform with tributes and clips of her from the Superman movies.